Blue Dragon
Glaucus atlanticus
Markings and exact colorations may vary.
A tiny blue-and-silver sea slug with feathery arms that can deliver a powerful sting.
- Typical size
- Up to 1.2 in
- How often it turns up
- Rare
- Collecting
- Check local rules
- Handling
- Possibly venomous
This is a living animal. Photograph it and leave it where you found it, or ease it back into the water.
Do not touch, even if it looks dead. It carries man o' war stinging cells and can sting more strongly than its prey. Photograph only.
How to tell it apart
- Small blue-and-silver striped body
- Three pairs of feathery finger-like clusters along the sides
- Washes up with man o' war or blue buttons
Where to find these in Florida
Beaches rated very good or excellent for tidepool life. Each page shows today’s score, the best window and access details.
- Bathtub Reef Beach · Stuart
- Anne's Beach · Islamorada
- Bahia Honda State Park · Big Pine Key
- Bathtub Beach · Stuart
- Caspersen Beach · Venice
- Curry Hammock State Park · Marathon
- Fort Zachary Taylor Historic State Park · Key West
- Harry Harris Park · Tavernier
- Higgs Beach · Key West
- John Pennekamp Coral Reef State Park · Key Largo
- Long Key State Park · Long Key
- Marineland Beach · Marineland
Found one?
Photograph it and BeachNut ranks the likely matches with a confidence read, then logs it to your collection with the beach and date.
Browsing beaches and the full field guide is free. A free account logs unlimited finds and gives you three photo identifications a day.
Commonly confused with
Blue ButtonPorpita porpita
Blue button is a flat round disc; blue dragon is a slug with feathery arms — and it stings hard.
More tidepool life in the field guide
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